ABSTRACT
Lolitrem B, a causative toxin for ryegrass staggers, is produced by Neotyphodium lolii infecting perennial ryegrass (Lolium perenne). Japanese black cattle have been suspected to be more sensitive to lolitrem B than to other strains, and there has been a concern about the public health hazard of eating beef contaminated with lolitrem B. We carried out a feeding experiment to examine the sensitivity of Japanese black cattle to lolitrem B and the residual level of lolitrem B in several animal tissues. Japanese black steers were fed a 0, 500, 750, 1000, 1500 or 2000 µg kg(-1) diet of lolitrem B provided by endophyte-infected perennial ryegrass straw for 12 weeks. All six animals in the 2000 µg kg(-1) diet group exhibited ryegrass staggers symptoms. Furthermore, two out of three animals in the 1500 µg kg(-1) diet group, three out of six animals in the 1000 µg kg(-1) diet group and one out of three animals in the 750 µg kg(-1) diet group presented clinical signs of ryegrass staggers. These results suggest that a daily intake of 18 µg kg(-1) body weight of lolitrem B can produce ryegrass staggers in Japanese black steers. Perirenal fat tissues of the steers from those groups having one or more animals exhibiting ryegrass staggers symptoms contained approximately 150 ng g(-1) of lolitrem B, while only small amounts of lolitrem B were detected in muscle, liver and kidney. Because the residual amount of lolitrem B in tissues of Japanese black cattle is small, the exposure to lolitrem B in consumers of the beef is likely to be low.
Subject(s)
Cattle Diseases/chemically induced , Indole Alkaloids/pharmacokinetics , Indole Alkaloids/toxicity , Mycotoxins/pharmacokinetics , Mycotoxins/toxicity , Adipose Tissue/chemistry , Adipose Tissue/metabolism , Animal Feed/analysis , Animals , Cattle , Diet/veterinary , Dose-Response Relationship, Drug , Food Contamination , Humans , Indole Alkaloids/administration & dosage , Male , Muscle, Skeletal/chemistry , Muscle, Skeletal/metabolism , Mycotoxins/administration & dosage , Risk FactorsABSTRACT
This study examined the influence of transgenic event CBH (StarLink; SL)-derived hybrid corn on growth, health and physiological functions of pigs, as well as the possibility of transferring the cry9C gene or Cry9C protein to the blood, liver or muscles, in comparison with pigs fed a diet with non-transgenic (isogenic) corn (non-SL). The diet for the SL group was composed of 70% SL corn, and the diet for the non-SL group was composed of 70% non-SL corn. Forty pigs approximately 3 months in age were used in the current experiment. After the pigs were acclimatized to their environment for 7 days, they were fed piglet diets for 7 weeks, and afterwards fed growing-finishing diets until the end of the experiment. There were no significant differences in bodyweight gain, feed intake or feed conversion ratio between the pigs fed SL diet and those of non-SL diet. No abnormalities were observed in the health conditions of either the SL or the non-SL group. Moreover, no significant differences were observed between the two groups in hematological values, histopathological examination and necropsy findings. Although the serum biochemical values within each group were normal, the blood urea nitrogen values of the SL group showed a tendency to be slightly higher than those of the non-SL group. Also, the blood glucose values of the SL group were significantly lower than those of the non-SL group. However, the cause of the significant differences in the blood glucose values between the two groups is unknown. The PCR and ELISA did not detect the cry9C gene and Cry9C protein in the blood, liver or muscles of the pigs at the end of the experiment.
